Numerous attempts have been made and means proposed to eliminate or lessen many of the negative and dangerous effects from the consumption of nicotine and cannabis. Herein, nicotine is used to refer to itself, the major active substance in tobacco. Also it is intended to refer to all relevant tobacco-like products, nicotine salts, derivatives, precursors, and those substances known to have nicotine-like effects, such as lobeline, the tetramethylamonium family of salts, etc. Cannabis is intended to refer to all of the relevant known substances found in the Cannabis family of plants. Also, it is intended to include all relevant cannabis-like products, natural and synthetic cannabis isomers, and other derivatives, precursors, metabolites, etc., or related substances having cannabis like effects.
While many means of consumption are known, not all are practical. The act of smoking, thus far, has proven to be one of the most direct, simple, and convenient means of intake of these substances.
Smoking involves the direct combustion of tobacco or cannabis and subsequent inhalation of the resulting smoke. This smoke may be inhaled directly in its raw form, immediately, or after it has been processed, filtered, or stored for use at a later time. As the active agents of tobacco and cannabis are relatively potent substances, only small amounts carried directly into the alveoli of the lungs and subsequently diffused into the bloodstream are needed to provide effect. As a result of this nearly direct access to the bloodstream, the relatively compact, simple to use, mild tasting, and yet potent means of consumption provided generally by smoking, and more specifically by the cigarette, in one form or another, has become the most popular means of tobacco and cannabis consumption, worldwide.
This does not include, however, the recent exception of cannabis preparations used medically in the United States. The most common of these is a capsule taken orally.
Smoking is not without its inherent problems, virtually all of which are well known and documented. For these reasons, smoking is not an approved medical means for the administration of any substance.
One of the major problems of smoking is the process of combustion itself required to produce the smoke for consumption. Kummel, in 1957, proposed the storage of compressed smoke for later use, thereby eliminating the need for combustion at the time of consumption. This means of consumption is not without disadvantage, however, in that the "tar", unwanted gases, and other byproducts of combustion are included in the smoke inhaled by the user.
The filtration and/or processing of smoke by all but the most esoteric means is both complex and incomplete. Known practical means such as cigarette filters, though widespread in use, have not been perfected. Additionally, they are almost totally ineffective against combustion gases without removing all other components simultaneously. "Perfect" filtration of stored or raw smoke, by measurement, would be exceedingly difficult to effect, and highly inefficient in the use of raw product, if attempted in practice. Combustion gases, which are present in stored smoke as they are in raw smoke, are likewise difficult to remove from all other components in the smoke without dramatically effecting the character and composition of the remaining components.
Proposals and experimentation, to extract or synthesize the active and desirable components and other additives judged necessary in the practice of the art to prepare any of various smokeless inhalable aerosol formulations, have been proposed and examined by Collier, Herxheimer, Olsen, Vachon, Tashkin, Jacobs (application Ser. No. 830,052, now abandoned), and others. Collier first proposed this means for the substitution of smoking tobacco in 1964. Herxheimer, in 1967, experimented with inhalable nicotine using a "Medihaler" aerosol dispenser and found it to be as physiologically effective as a means of providing inhalable nicotine to a user, as is a cigarette, without the necessity of producing or inhaling smoke. Likewise, in 1977, Gori proposed the effectiveness of a smokeless nicotine aerosol through use of a Babbington Inhaler.
Olsen developed a self propelled inhalable aerosol of delta-9-tetrahydrocannabinol and evaluated it on a preliminary basis in 1975. The effectiveness of delta-9-tetrahydrocannabinol in an inhalable aerosol, as a bronchodilator, was demonstrated through use of a cascade nebulizer by Vachon in 1976. Its bronchodilator effects were earlier verified by both Tashkin and Vachon, in smoke, in 1973.
Many methods of aerosol production described in the literature (i.e., ultrasonic nebulization, cascade nebulization, etc.) are effective in providing the user with a smokeless aerosol of sufficiently fine particle size to negotiate entry into the alveoli of the lungs in the same manner as smoke. They are, however, impractical for other than experimental use, due to their expense, size, lack of portability, and complexity.
The effectiveness of the various self propelled aerosol formulations examined, containing only liquid components, has varied. Depending upon the active agent under investigation, formulation involved, and intended purpose, estimated performance has ranged from marginal to good.
The inclusion of a finely divided, biologically inhert and/or compatable solid particulate fraction into a self propelled aerosol formulation is known to the art of self propelled inhalable aerosol medications. These include inhalable bronchodialators and steriods for asthma, and other formulations. It has proven to be both a feasable and practical process for the production of self propelled aerosols of sufficiently fine particle size to reach the alveoli of the lungs and, thereby, to deliver the active agent contained within or upon them to both the entire respiratory tree and, subsequently, the bloodstream.